This issue is a variant of Avengers (Marvel, 2010 series) #1 [Standard Cover]. There exist further variants.
This could be the "Los Angeles Rock'n Comic Con 2010" version but would need confirmation.
Prologue and Chapter 1. Continued in New Avengers (Marvel, 2010 series) #1. Illustrations reprinted from Avengers Classic (Marvel, 2007 series) #1 and The Avengers (Marvel, 1963 series) #1.